Why have an extra attack when you just want to drop it?
Begining at 1st level, once per turn, when you take the attack action, you can forego one of your attacks to use one of the following shouts instead:
replace with
Beginning at 1st level, once per turn, when you take the attack action, you can use one of the following shouts:
If you want to delay the two-tap to level 5:
Beginning at 1st level you can do one of the following shouts as an action. Starting at 5th level when you take the attack action, you can also shout as part of the attack.
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Replace Shout with Command? Or Tactical Command?
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"An effect a save can end" is that standard 5e verbage? (It sounds 4e)
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Once per turn, if you inflict damage to a creature while you have advantage, or it is within 5 feet of you or an ally, you generate a number of Insight Dice as shown to the Insight Dice collumn of the Warlord table. Unused Insight Dice dissapear at the start of your turn. An ally that makes an attack against the same creature you hit to generate your Insight Dice can choose to expend any number of Insight Dice and add them to the attack's damage roll. The decision to spend Insight Dice must be done before the attack is rolled.
Did you mean "5 feet of you or an ally" or "within 5 feet of you and an ally"? The second matches sneak attack. The first means that it is basically all melee attacks, plus ranged attacks where an ally is adjacent to it, plus attacks where you have advantage; at that point, the number of situation is so broad that it should be "always".
What happens if we apply the Insight Dice on a creature?
Once per turn when you damage a creature with an attack, you can apply your Insight Dice to it. If it already has Insight Dice on it, they are replaced. An ally who attacks a creature with Insight Dice on it may choose to exploit the Insight. If they do so, they have advantage on the attack roll, and add the Insight Dice to the damage of the attack. Regardless, the Insight Dice are consumed. Insight Dice on a creature disappear after 1 minute, or if the Warlord is incapacitated.
I added in "advantage", because it fits the idea of insight and is very warlord-ish, and makes it a bit less likely to be wasted.
Also note that in this version, you can deploy dice and they accumulate. Applying more than 1 per round is hard, however.
Astronomical Luck (7 dice) Select one ally that can see you within 10 feet. That ally may immediately spend its reaction to make a weapon attack. This attack can score a critical hit on a roll of 18-20. If the attack misses, the target of the attack has advantage on their next attack roll against your ally.
If you did the "insight dice on creature", you'd (a) have the target be the creature with the dice, and (b) the 10' range is from said creature or from you. (Support for archer warlords or front-liners).
I'm not sure how this is fluffed as a signal -- luck as a signal?
Benefits:
1. Convert reaction to an attack
2. Wide critical hit boost. If they have advantage, this is 18% (just over 1/6) worth of critical hit boost over a normal attack without it.
Critical Target (2 dice) Select one ally that can see you within 30 feet. If that ally inflicts damage to an enemy on their next turn, they gain temporary hit points equal to your proficiency bonus.
Not enough temporary HP? At low levels is 3 temporary HP, a high levels is 6. "an enemy" not the enemy the warlord hurt to get the dice?
Maybe roll the dice for the temporary HP, and add charisma?
To tighten up balance past "it feels good", we need a formal "damage budget" for burning bonus action and/or dice. What is the bonus action "worth"? What are burned dice "work"?
Escape Route (2 dice) Select one ally that can see you within 30 feet. On their turn, that ally may take the Disengage action as a bonus action.
Neat.
Flaw in the Armor (1 dice) Select one ally that see you within 15 feet. They gain advantage on their next melee weapon attack.
Very cheap in dice.
Flaw in the Defenses (1 dice) Select one ally that see you within 15 feet. They gain advantage on their next ranged weapon attack or the attack rolls of a cantrip.
I'm not sure why these are two different features. They have the same fluff and nearly identical crunch.
Form Up (1 dice or more) Select a number of ally that can see you within 30 equal to the number of Insight Dice spent. Until the start of your next turn, while those allies are within 5 feet of you and you are not prone, restrained or incapacitated, they gain a +2 bonus to AC. You must be wielding a shield to use this signal.
Form Up should permit non-block formations. "Within 5' or within 5' of another character who qualifies for the Form Up bonus"?
Hit a Nerve (5 dice) Select one ally that can see you within 30 feet. Once on their next turn, they can attempt to stun an enemy with their melee weapon attack. The ally must decide before making the attack roll. If the attack hits, all damage the attack inflicts is reduced to zero8 and the target is stunned until the start of your ally's following turn. If the attack misses, the target of the attack has advantage on their next attack roll against your ally.
I think I wrote this elsewhere, but hits don't cause stuns in 5e. Creatures with legendary resistances need to be able to shrug off stuns to be balanced against parties.
And they cannot shrug off hits.
5e assumes hits (from PCs) deal modest damage (5-25), except crits, smites and sneak attack type things. They don't shut the target down.
(You'll note that grappling, as a pseudo-attack, can often provide nasty status conditions (immobalize and with UA feats restrained and with shove a prone) that don't involve saves. That is why grapple is crazy strong against larger or smaller boss monsters. Slipping something even stronger than UA-enhanced grapple in here is probably not a great idea for balanced homebrew.)
Veteran Poise
You need to ensure this doesn't give 3x proficiency with expertise.